This is a tough yet very good question... Some people have said how the soft one swims like a dream from their experience... I think it would be best to be a little bit more patient and wait to hear from more people who experienced the monofin at its different levels of hardness just to be sure... Also they have said that it runs small so go 2 to 3 sizes up from your actual foot size(foam neoprene booties will be required obviously for this) best of luck

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